Collapsible book rack



Feb. 22, 1966 A. R. PERINI COLLAPSIBLE BOOK RACK 2 Sheets-Sheet 1 Filed June 30, 1964 Anthony R- Peri/Ii INVENTOR.

Feb. 22, 1966 A. R. PERIN] COLLAPSIBLE BOOK RACK 2 Sheets-Sheet 2 Filed June 30, 1964 Anthony H- Per/n/ INVENTOR.

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andfimfim IIP'IQIII'II United States Patent 3,236,387 COLLAPSIBLE BOOK RACK Anthony R. Perini, P.0. Box 579, New Bedford, Mass. Filed June 30, 1964, Ser. No. 379,330 12 Claims. (Cl. 21142) This invention relates to a novel leg-supported openwork dual frame structure which is functionally designed and structurally adapted to provide a crib-type rack and is primarily, but not necessarily, intended to serve as a grouping and racking stand for books.

The present invention bears resemblance to and is a meritorious improvement upon my prior Patent 3,095,974, dated July 2, 1963, and which has to do with a crib-type collapsible book rack characterized by two rod-equipped frame units having crossed legs providing X-shaped end members. The paired crossed legs have their crossed portions separably bolted together. In carrying out the herein disclosed improved concept the nut held bolts are dispensed with and the crossed mortised portions of the legs coact in an improved manner. With this in view the legs at one end only of the rack are positively interlocked. To this end, one leg has a spring loaded trigger latch; that is, a unique block-like member substantially housed in a pocket or cavity and with a projecting marginal corner which serves not only as a finger operated trigger but also as a detent, the latter being releasably seatable in a kerf serving as a shouldered holder for said latch.

Novelty is predicated not only on the stated trigger latch for a crib-type book rack but upon any equivalent leg structure or the like wherein crossed legs or the like are notched or mortised with a spring biased latch arrangment suitably usable to separably join the component parts together and wherein a minimal projecting portion Constitutes a finger released trigger fitting releasably into detent or retainer means therefor.

Another improvement is directed to a structure of the type herein shown and which, generally speaking, relates to support means, whether a stand, rack or an equivalent arrangement, which is characterized by a first elongated rod member, a companion second elongated rod member which is spaced from and parallel to the first rod member and preferably commensurate in length therewith. These supported rod members, more specifically, dowels or the like, serve to accommodatingly support a pair of adjustably shiftable slides. These slides are at right angles to the rod members and span the space between the rod members and have terminal end portions which are slidingly mounted on and are thus operatively connected to their respective rod members. At least one of these rod members is rotatably mounted on the aforementioned support means and is turnable in and relative to the end of the slide, or slides, which are cooperably shiftable thereon. This latter rod member is provided on one longitudinal peripheral surface with longitudinally spaced selectively usable cutouts which constitute keeper seats. One end of each slide has a resilient keeper which is adapted to snap into a selected keeper seat whereby to in this manner lock the slide in a given position on both rod members. It is within the purview of the invention to use either one slide or two slides, preferably two slides, and to utilize the slides as article clamping members.

More specifically the rod members are dowels which are suitably circular in cross-section. The respective or coacting ends of the aforementioned slides are apertured and the rod members or dowels pass through the respective apertured ends. T o the ends desired the keeper preferably comprises a fiat faced tongue which is fixed at one end, the other end being flexible and serving as the keeper proper. The keeper seats comprise recesses formed in said one peripheral surface and it is into these that the 3,236,387 Patented Feb. 22, 1966 ice keeper automatically snaps and retentively seats itself. With this construction one flat side of the tongue is accordingly adapted to ride uninterruptedly along the properly positioned smooth side of the peripheral surface; that is, when all of the keeper seats are turned away from and accordingly disaligned with the path of travel of the tongue.

From the foregoing it will be obvious that novelty is predicated on one smooth surfaced elongated dowel on the support, an opposed specially constructed companion dowel on the support and having notches therein for selective seating of the free end portion or keeper which is defined by the flat-faced springy or resilient tongue.

More particularly novelty is predicated on the aforementioned dual rod arrangement with the rods constructed as stated but preferably wherein the end portions of the rods are attached to crossed legs, the crossed legs and rods, in conjunction with supplemental fixedly mounted rods primarily for feasible and practical use in a crib-type book rack.

Novelty is predicated on the combination with a flatfaced tongue of a manually actuatable trip means. This means is carried by and is operatively mounted on one end of the slide and is releasably engageable with the keeper or tongue. It is so arranged and available that it functions to force the keeper out of the keeper seat in which it is temporarily seated so as to effect the desired keeper releasing and slide adjusting step.

In carrying out a preferred embodiment of the invention the trip means comprises a simple pin which is movably mounted on one end of the slide, is disposed. at right angles to the plane of the cooperating flat side of the keeper with the result that the inner end of the pin constantly bears against the flat side while the outer end is exposed and is provided with an accessible fingergrip for adjustment and releasing requirements.

Then, too, novelty is predicated on portable support means, for example, the stand or rack shown which is provided with a first elongated dowel supported horizontally atop the support means. This dowel cooperates with a second elongated dowel which is also horizontally supported atop the support means but is spaced. from and parallel to the first dowel. The first dowel has uninterruptedly smooth surfaces while the peripheral surface of the second dowel has one major longitudinal side thereof smooth but the other diametrically opposite side provided with recesses which constitute keeper seats. The arrangement serves to fittingly accommodate a pair of like article embracing and clamping slides. These slides are preferably in the form of elongated fiat-sided bars which bridge the space between the dowels and have their end portions apertured and slidingly encompassing and adjustably shiftable back and forth and. relative to each other on the supporting dowels. The ends of the slides which are iadjacent to the recessed dowel are provided with springy tongues which are preferably associated with the apertured portion. These tongues provide keepers and the keepers are seatable in selectively usable keeper seats.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a view in perspective of a portable folding or collapsible book rack constructed in accordance with the principles of the invention and. showing the same set up for use and with the aforementioned slides widely spaced apart at the opposite left and right end portions of the rack;

FIGURE 2 is a central transverse cross-sectional view of the structure shown in FIGURE 1;

v FIGURE 3 is an enlarged view taken on the plane of the section line 33 of FIGURE 1 looking in the direction of the arrows and showing the aforementioned springy tongue or keeper means, how it seats in a keeper seat and how the available releasing and adjusting pin means cooperates therewith;

FIGURE 4 is a fragmentary view with parts in section and elevation taken on the plane of the section line 4-4 of FIGURE 1;

FIGURE 5 is also a fragmentary sectional and elevational view taken on the irregular section line 55 of FIGURE 4;

FIGURE 6 is a fragmentary view with parts in section and parts in elevation and suitably enlarged and taken on the plane of the section line 6-6 of FIGURE 1;

FIGURE 7 is an end elevation of the rack showing the manner in which the two frame units or leg frames are capable of being folded to assume a compact position for storage and carrying;

FIGURE 7A is a view based on FIGURE 7 and which shows the final step wherein the component parts are arranged in collapsed or folded relationship; and

FIGURE 8 is an enlarged perspective approximately on the same scale as FIGURE 1 showing how the component parts appear and coact when they are collapsed to assume the folded positions or relationship shown in FIGURE 7A.

By way of introduction to the description of the details it is to be reiterated that some other features of the overall concept, while ideal in the construction of the herein disclosed collapsible book rack are perhaps susceptible of use alone; for example, the tongue and pin assembly of FIGURE 3, the trigger latch arrangement and assembly of FIGURE 4 and the notched rod or dowel feature as will be hereinafter more clearly dwelled upon.

With respect to the general assembly and more particularly FIGURES 1 and 2, one frame unit of the book rack is denoted at A and the other frame unit at B. The unit A is characterized by a pair of spaced parallel duplicate end members constituting legs 11 the median portions of which are provided with suitably opening mortises or notches 12. The upper apertured end portions 14 of these legs are operatively mounted on the respective end portions of a horizontal intervening elongated dowel or rod member 18. Both legs are mounted in the same manner with the terminals of said end portions projecting outwardly and beyond the apertured end portions of the legs as shown at 16. With reference now to FIG- URE 2 in particular it will be seen that there is a lower rod member or dowel 20 which has its end portions fixedly mounted between the two legs 10. In addition there are two additional or intermediate rod members or dowels 24. Thus these two legs 10 are provided with fourdowels or rod members making up the rearward frame unit A. .The front or forward frame unit B is basically the same but has a pair of spaced somewhat shorter legs 22 whose upper ends are operatively mounted on the end portions of a forward dowel or rod member 26. There is a second rod member or dowel at 28 which is fixed between the median portions of the legs 22 and an intermediate dowel at 30. In addition there is a complemental lower rod member or dowel at 32 which is primarily a rigidifying brace. It follows that these two legs 22 and the dowels 26, 28, 30 and 32 constitute the primary components of the frame unit B. It will be noted, too, that the median portions of the legs 22 have suitably opening mortises or notches 34 which fittingly interlock with the aforementioned notches 12. It follows that when the two leg frames or units A and B are assembled and set up for use as shown in FIGS. 1 and 2, the notches 12 and 34 cooperate and consequently the paired legs 10 and 22 are in X-shaped relationship. With special reference to the upper rearward and forward dowels 18 and 26 it should be noted that the dowel 18 is smooth from end to end and consequently has no obstructions along the surfaces. On the other hand, the dowel 26 is provided along one peripheral side with a plurality of longitudinally spaced notches or cutouts which constitute keeper seats 36 which are selectively usable. The opposite side or peripheral surface 38 is smooth and unobstructed. With reference to FIGURE 6 it will be seen that the righthand end portion of the dowel 26 is specially mounted. That is to say, a hole 40 in the coacting leg 22 has a sleeve or bushing 42 fixed therein. This bushing has an axial bore for reception of a headed rigid assembling pin 43 which bridges the joint between the socketed righthand end portion of the dowel 26 and the lefthand end portion of the bushing 42, and serves to accommodate a headed nail 45 which passes through a hole in the assembling pin 43 and serves to mount and retain a knob-like fingergripping lever 46 which serves to oscillate the dowel 26 and pin 43. This lever is swingable back and forth in a substantially V-shaped recess 48 formed in the upper end of the leg whereby to permit the keeper notches to be turned to an in-use position or to an out-of-use position in a manner to be described.

With respect now to the left and right slides, which are commonly used as book clamps, these are the same in construction and may be used singly or collectively. Each slide is denoted by the numeral 50 and a description of one will suffice for both. The slide comprises a bar 52 of a length which spans the space between the forward and rearward dowels 26 and 18. The rearward laterally directed end portion 54 is provided with an aperture or hole 56 which can be slid freely back and forth on the dowel or rod 18. The lateral-1y directed downturned forward end 58 is of special construction. In addition to the aperture or hole (see FIG. 3) 60 it is provided with an enlarged slot portion 62 to accommodate a flat leaf spring or tongue. One end portion 64 is anchored and the other end portion in the enlarged end of the slot is flexible and constitutes a snap-type keeper 66 which can be engaged in a selected one of the keeper seats 36. The inherent tendency of the keeper is to cause it to drop into the seat selected. When it is desired to release it, release means is available. This comprises a simple pin 68 which has a pointed end engaging a Hat side of the leaf spring. There is a socket 70 provided and a bushing 72 is securely fitted therein and may if desired have a screw-threaded bore to accommodate the screw-threaded portion 74 of the headed end portion 76 of the trip pin. By screwing the pin in the keeper can be released from the seat in the manner shown in FIGURE 3. The median portion of the pin 15 provided with a reduced part to accommodate a washer 7 which constitutes a limit stop and which is engageable with an end portion of the plugged-in bushing.

As stated at the beginning of the specification it is desired to permit the crossed portions of the legs of the respective frame units to be bodily brought together and locked and to be readily separated to permit folding from the position show in FIG. 1 to the positions shown in FIGURES 7, 7A and the final step in FIGURE 8. To satisfactorily accomplish this a trigger latch is employed as shown in FIG. 4. This comprises a block or equivalent member 80 which is primarily concealed and operable in a cavity 82 which provides a pocket therefor. One corner of the block 84 is projectible beyond the open side of the cavity and this is accomplished by way of the coil spring 86 surrounding an anchor pin 88 with one end of the pin attached to the block, the other end abutting a wall of the cavity as shown at 90. The spring is angled over an abutment pin 92. When the structure is set up for use this trigger latch has a portion which is projectible into a kerf 93 which is provided in the coacting leg whereby to thus lock the crossed portions of the two legs together. This latch means is not used at the other end of the frame unit.

With reference again to FIGS. 1 and 2 where the rack is shown with the component parts assembled for use it will be evident that the two main frame units A and B assume a relationship to each other wherein the frame unit A (FIG. 2) inclines rearwardly and provides spaced parallel cooperating rods or dowels providing an openwork side of the book crib. The shorter legs of the frame unit B slant upwardly and forwardly and the cooperating intermediate portions of the respective legs and 22 overlap or are crossed with the mortises or notches 12 and 34 engaged to provide adequate support and with the result that the dowels 26, 3t) and 28 cooperate with the dowels to the rear in defining the open top book crib with a book placeable therein as shown in phantom lines in FIG. 2. Assuming that there is a group of books it will be evident that the two slides 50 can be shifted toward each other to clampingly engage the books at the center of the rack. The rearward end portions of the slides 50 slide freely along the rod or dowel 18. The forward ends can be adjustably locked in any desired position by way of the keeper notches 36 and the keeper tongues 66 which seat in the notches as shown in FIG. 3. It is within the purview of the invention to turn the rod 26 by catching hold of the fingergripping lever 46 and swinging it either forwardly or rearwardly. This brings the notches to a position of disalignment with the keeper tongue whereupon the tongue can then slide freely along the unnotched peripheral surface of this dowel or rod 26. The available pin means in FIG. 3 can be used for releasing the keeper tongues to facilitate turning and operation of the dowel 26 by the lever 46. In any event it will be clear that this construction facilitates the slides being shifted back and forth and positively locked in whatever position desired.

When the device is not in use the rigger latch means of FIGURE 4 is available to permit the legs of the respective frame units to be parted. It will be noted in this connection that the exposed corner portions 84 of the trigger latch can be pressed with ones finger and the latch can be pushed in, that is, disengaged from the kerf 93. When the latch is thus released the legs at both ends of the structure can be parted and the two frame units A and B can be folded. First the frame unit B can be placed on the ground or other surface after which the slides 56 can be folded down on top of it as shown in FIGURE 7A. Then the rear frame unit A can be swung up and over to the left as indicated in phantom lines in FIGURE 7A in order to thus stack the components one on top of the other for collapsed or folded handling for shipping, transportation or storage. FIGURE 1 shows the device fully set up and FIGURE 8 shows it folded.

It is to be noted that the terminal ends 16 of the uppermost dowel 18 extend outwardly beyond the legs 10 of the rearward frame unit A, whereby to permit the rack to be hung and suspended at a desired level from hanger hooks, clips or the like on a relatively stationary support wall as shown, for example, in FIG. 6 of my prior Patent 3,095,974. Then, too it also is to be noted that the terminal end portions 33 of the brace rod 32 likewise extend beyond the respective legs 22 of the forward frame unit B. Accordingly, and inasmuch as the stabilizing rod 32 is parallel with and in a plane directly below the upper rod or dowel 18 (see FIG. 2) the respectively extending upper and lower ends 16 and 33 are thought to be of exceptional value should one desire to elevate and suspend my unique crib-like rack on merchant or military seacraft bulkhead or aircraft walls (not shown). It is not difiicult to visualize how the rack would, unless restrained, pivot and swing outwardly and inwardly on a pair of books on a vessel bulkhead if only the extensions 16 were used. On the other hand, by combining the extended ends 33 with the ends 16 said ends 33 can be hooked to the bulkhead (similarly to manner shown in my aforementioned Patent 3,095,974) thus providing novel holddown means and minimizing the likelihood of the books catapulting from the crib.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A structure of the class described comprising, in combination, support means embodying a first elongated rod member, a second elongated rod member spaced from and parallel to said first rod member and commensurate in length therewith, and an adjustably shiftable slide at right angles to said rod members spanning the space between said rod members, and having terminal end portions which are slidingly keyed on and thus linked to their respective rod members, one of said rod members being rotatably mounted on said support means and turna-ble in and relative to the end of said slide which is shiftable on said one rod member, the latter rod member being provided on one lengthwise peripheral surface with longitudinally spaced selectively usable keeper seats, and said one end of said slide having a resilient keeper which is adapted to snap into a selected keeper seat whereby to thus lock said slide in a given position on said rod members, said rod :members comprising dowels which are circular in cross-section, the coacting ends of said slides being apertured and said rod members passing through the respective apertured ends, said keeper comprising a fiat-faced tongue fixed at one end, the other end being flexibly free and defining the keeper proper, said keeper seats comprising recesse formed in said one peripheral surface and into which said keeper automatically snaps and retentively seats itself, one flat side of said tongue being adapted to ride uninterruptedly along the smooth side of said peripheral surface when the keeper seats are turned from and disalign-ed with the path of travel of said tongue, and manually actuatable trip means carried by and operatively mounted on said one end of said slide and releasably engageable with said keeper and functioning to force the latter out of the keeper seat in which it is temporarily seated to effect the release step desired.

2. A structure of the class described comprising, in combination, support means embodying a first elongated rod member, a second elongated rod member spaced from and parallel to said first rod member and commensurate in length therewith, a slide disposed at right angles to said rod members, spanning the space between said rod members, and having terminal end portions slidingly keyed on their respective rod members, one of said rod members being rotatably mounted on said support means and turnable in and relative to the end of said slide which is shiftable on said one rod member, the latter rod member being provided on one lengthwise peripheral surface with longitudinally spaced selectively usable keeper seats, said one end of said slide having a resilient keeper adapted to snap into a selected keeper seat in a manner to lock said slide in a given position on said rod members, said rod members comprising dowels, the coacting ends of said slides being apertured and said rod members passing through the respective apertured ends, said keeper comprising a springy tongue fixed at one end, the other end being flexibly free and defining the keeper proper, said keeper seats comprising recesses formed in said one peripheral surface and into which said keeper automatically snaps and retentively seats itself, one side of said tongue being adapted to ride uninterruptedly along the smooth side of said peripheral surface when the keeper seats are turned from and disaligned with the path of travel of said tongue, and manually actuatable trip means carried by and operatively mounted on said one end of said slide and releasably engeable with said keeper and functioning to force the latter out of the keeper seat in which it is temporarily seated.

3. The structure defined in claim 1, and wherein said trip means comprises a pin movably mounted on said one end of said slide and disposed at right angles to the plane of a cooperating flat side of said keeper with an inner end thereof constantly bearing against said flat side, the outer end of said pin having an accessible fingergrip.

4. The structure according to claim 1, and wherein said one end of said slide has a socket with a bushing lodged and secured therein, said pin being adjustably mounted in the bore of said bushing, and a median portion of said pin having a limit stop abutting a cooperating end of said bushing and being normally held by the spring action of the tongue.

5. A structure of the class described comprising portable support means, a first elongated dowel suppo-rted horizontally atop said support means, a second elongated dowel complemental to and also supported horizontally atop said support means and spaced from and parallel to said first dowel, the entire peripheral surface of the latter dowel being uinterruptedly smooth, the peripheral surface of said second dowel having one longitudinal side thereof provided with longitudinally spaced recesses providing selectively usable keeper seats, a pair of like article embracing and clamping slides bridging the space between said dowels and having their end portions apertured and slidingly encompassing and adjustably shiftable back and forth and relative to each other on said dowels, the ends of said slides adjacent to the recessed dowel having springy tongues in their apertured portions, said tongues providing keepers and said keepers being seatable in selected ones of said keeper seats.

6. The structure according to claim 5, and wherein said support means embodies frame units having vertical uprights, the end portions of said second dowel being rotatable in bearings provided therefor, one of said end portions having a lateral lever which can be caught hold of for purposes of rocking said second dowel and thus positioning the keeper seats in position out of alignment with said keeper.

7. The structure according to claim 5, and wherein said support means comprises a book rack, said slides each comprising an elongated bar having opposed flat vertical book clamping surfaces.

8. The structure defined in claim 5, and wherein said support means comprises a portable openwork crib-like rack for reception of books and the like, said rack having legs separably joined to each other and being collapsible, said legs having upper ends pivota-lly joined to the respectively cooperable ends of said first and second dowels.

9. A portable book rack comprising a pair of vertical spaced parallel X-shaped leg frames, each leg frame comprising a pair of crossed legs, a first pair of relatively low horizontal parallel contiguous rod members having their respective outer ends connected to the respective legs of the crossed portions of the respective leg frames, a second pair of upper horizontal rod members having their end portions connected to the upper ends of the respective legs of the respective leg frames, a plurality of intermediate rod members arranged in planes between the upper and lower rod members and connected at their ends to their respective legs of the respective leg frames and providing a crib-like book rack, and a pair of .bar members disposed at right angles to and having apertured end portions slidable along said upper rod members, bridging the space between the upper rod members, and being adjustable along said rod members toward and from each other, the crossed portions of said legs having registering interlocking notches, one of the legs being provided adjacent one notch with a spring loaded trigger latch releasably engageable with retaining shoulders provided therefor on the companion leg.

10. The structure defined in claim 9, and wherein said trigger latch is operably mounted in a cavity provided therefor in said one leg, the major portion of said latch being concealed and a minimal marginal portion being exposed at the juncture of the crossed portions and providing a trigger for finger control and operation, whereby to permit the legs to be disconnected f-or collapsing the overall rack.

11. A collapsible frame structure having a pair of like legs having median portions mortised, the mortised portions being sepa-rably fitted together .and permitting the legs to be detachably interlocked in X-shaped relationship, one leg having a pocket-like cavity in line with its adjacent mortise, a spring biased trigger latch substantially confined in the pocket port-ion of said cavity, the other leg having a kerf adjacent its mortise, said kerf providing a shouldered retainer for a trippable portion of said latch.

12. The structure defined in claim 11, and wherein said latch embodies a block-like member, a marginal corner of which defines the said trippable portion.

References Cited by the Examiner UNITED STATES PATENTS 217,203 7/1879 Davis 248-164 535,082 3/1895 Snell 248-354 2,376,716 5/1945 Odin 248-407 3,095,974 7/1963 P rini 211-42 CLAUDE A. LE ROY, Primary Examiner. 

1. A STRUCTURE OF THE CLASS DESCRIBED COMPRISING, IN COMBINATION, SUPPORT MEANS EMBODYING A FIRST ELONGATED ROD MEMBER, A SECOND ELONGATED ROD MEMBER SPACED FROM AND PARALLEL TO SAID FIRST ROD MEMBER AND COMMENSURATE IN LENGTH THEREWITH, AND AN ADJUSTABLY SHIFTABLE SLIDE AT RIGHT ANGLES TO SAID ROD MEMBERS SPANNING THE SPACE BETWEEN SAID ROD MEMBERS, AND HAVING TERMINAL END PORTIONS WHICH ARE SLIDINGLY KEYED ON AND THUS LINKED TO THEIR RESPECTIVE ROD MEMBERS, ONE OF SAID ROD MEMBERS BEING ROTATABLY MOUNTED ON SAID SUPPORT MEANS AND TURNABLE IN AND RELATIVE TO THE END OF SAID SLIDE WHICH IS SHIFTABLE ON SAID ONE ROD MEMBER, THE LATTER ROD MEMBER BEING PROVIDED ON ONE LENGTHWISE PERIPHERAL SURFACE WITH LONGITUDINALLY SPACED SELECTIVELY USABLE KEEPER SEATS, AND SAID ONE END OF SAID SLIDE HAVING A RESILIENT KEEPER WHICH IS ADAPTED TO SNAP INTO A SELECTED KEEPER SEAT WHEREBY TO THUS LOCK SAID SLIDE IN A GIVEN POSITION ON SAID ROD MEMBERS, SAID ROD MEMBERS COMPRISING DOWELS WHICH ARE CIRCULAR IN CROSS-SECTION, THE COACTING ENDS OF SAID SLIDES BEING APERTURED AND SAID ROD MEMBERS, PASSING THROUGH THE RESPECTIVE APERTURED ENDS, SAID KEEPER COMPRISING A FLAT-FACED TONGUE FIXED AT ONE END, THE OTHER END BEING FLEXIBLE FREE AND DEFINING THE KEEPER PROPER, SAID KEEPER SEATS COMPRISING RECESSES FORMED IN SAID ONE PERIPHERAL SURFACE AND INTO WHICH SAID KEEPER AUTOMATICALLY SNAPS AND RETENTIVELY SEATS ITSELF, ONE FLAT SIDE OF SAID TONGUE BEING ADAPTED TO RIDE UNINTERRUPTEDLY ALONG THE SMOOTH SIDE OF SAID PERIPHERAL SURFACE WHEN THE KEEPER SEATS ARE TURNED FROM AND DISALIGNED WITH THE PATH OF TRAVEL OF SAID TONGUE, AND MANUALLY ACTUATABLE TRIP MEANS CARRIED BY AND OPERATIVELY MOUNTED ON SAID ONE END OF SAID SLIDE AND RELEASABLY ENGAGEABLE WITH SAID KEEPER AND FUNCTIONING TO FORCE THE LATTER OUT OF THE KEEPER SEAT IN WHICH IT IS TEMPORARILY SEATED TO EFFECT THE RELEASE STEP DESIRED. 